Piano action



F. C. SOCIN May 25, 1948.

PIANO ACTION Filed June 20 1945 2 Sheets-Sheet 2 Patented May 25, 1948 UNITED STATES PATENT CFFICE PIANO ACTION Francis C. Socin, St. Charles Township, Kane County, Ill., assignor to The Rudolph Wurlitzer Company, Chicago, Ill., a corporation Application .lune 20, 1945, Serial No. 600,522

7 Claims. l

This invention relates to a piano action, and particularly a compact, so-called compressed grand piano action. A

One purpose of the invention is to provide an action adapted for use in a square piano wherein it may be tted to the front portion of the piano ahead of the sounding board with a minimum of over all depth in a piano of this type. However, features of the invention hereafter referred to may be similarly embodied in actions applicable to other types of pianos.

One feature of the invention resides in a double-acting spring associated with and acting upon both the wippen and the jack. This doubleacting spring is so formed and arranged as to exert tension in two directions, exerting downward spring pressure on the wippen and laterallydirected spring tension on the jack to simultaneously and through the same spring action tend to return them to rest position after actuation. By means of such double-acting spring the repetition qualities of the piano are improved, due to the rapidity with which the spring causes the wippen and jack to resume their rest positions.

Another feature of the invention resides in an improved flexible jack having a pivotal link connection between the wippen and hammer. To assure positive action and the desired repetition, a shoulder isr provided on the jack member to limit its movement in one direction and provide a cushioned seat when in striking position, While permitting flexing to hammer let-01T position.

A still further feature of the invention resides in the provision of an adjustable flange formed of a looped metal strap adapted to be secured to the action rail to provide a hinged support and connection for an operating part, such as the wippen. Wherein the angular relation between the hammer lever and wippen relative to the action rails may vary in accordance with the relation of the keys to the strings, such variation and angular relation may be readily effected by bending or twisting the metal iiange. In this manner, the looped bearing end of the metal flange for receiving the hinge pin may be bent out of alignment with the rail to provide a hinge support at any desired angle.

Another feature of this invention resides in the character of the action brackets which support the action rails. In a compressed grand or square piano it is necessary that the action rails extend at different angles to the key-board, and therefore require angularly displaced supporting brackets. It has accordingly been found desirable to construct the action brackets of metal which is bendable to shape so that one form of bracket may be bent to the desiredangle and thereby eliminate the necessity of providing a plurality of brackets of different shape.

The full nature of the invention will be understood from the accompanying drawing and the following description and claims:

Fig. l is a side elevation showing one unit of the action in rest position, the supporting rails and parts of the piano structure being shown in section.

Fig. 2 is the sameas Fig. 1 showing a portion of the action in striking or actuated position.

Fig. 3 is a diagrammatic illustration of a part of a piano structure showing the angular relation of the action units relative to the action rails.

Fig. 4 is a plan view of a portion of the action rail and its pivotally supported member extending atan angle thereto.

Fig. 5 is a section through the action rail showing an end view of a twisted iiange.

Fig. 6 is a iront elevationv of a flange and supported member with a portion thereof broken away.

In the drawings there is shown, for the purpose of illustrating one application of the invention, a piano structure having a key bed I0, a key board II, and piano keys I2 .pivotally supported on the said key bed in the usual manner. The frame structure of the piano supports a forward pin block I3 supporting the forward portion of the string plate I4, upon which the piano strings I5 are carried. This portion of the structure and pin block is enclosed by a iront panel I6. Rearwardly o'f the action the :frame structure supports and includes the post or beam I'I. Supported by a series of action brackets I9a, there are action rails I9 and 20. SaidA brackets are of bendable metal so that they may be bent to extend at such angles. as to support the rails in their respective angular relation to the key bed. The action rail 2l is secured to the forward side of the post I'I.

Pivotally mounted on the liange 20u carried by the action rail 20 there is a hammer lever 22 extending rearwardly and downwardly therefrom to rest upon the action rail I9 when in rest position. Said hammer lever carries the hammer 23 in position to strike the piano string I5.

Pivotally supported by the action rail I9 through an angularly adjustable'ange 24 there is a wippen 25 extending substantially horizontally and forwardlyfrom' said rail in position to 3 be engaged and actuated by the capstan screw 26 carried on the rear end portion of the key l2.

The free or actuating end of the wippen carries a exible jack or fly comprising the jack member 21 and link member 28. The lower end of the jack member is pivotally connected with the free end of the Wippen, the upper end thereof being pivotally connected through the link member with the hammer lever 22. The end of the jack member pivoted to the wippen is provided with a let-off head 29 engageable with the regulating button 30 adjustably mounted upon the action rail 20. The opposite end of the jack member 21 is formed .or shaped with an upwardly protruding shoulder 3l so formed and shaped as to provide a seat for the link member 28 when the jack is in rest position. Said shoulder is provided with a suitable pad and is adapted to limit the iiexing movement of the jack in returning to rest position and maintain the `iack members in proper alignment for repeated strokes in transmitting the strikingv action from the wippen to the hammer.

For providing maximum ilexibility and repetition of the action, there is provided a doubleacting spring 32. @ne end of said spring is anchored at 32d to the wippen action rail i9 by a pin or any suitable means, while the other end thereof is hooked -into a cord 33 carried by the jack member 21 near the link member 28. Intermediate the ends ofy the spring it is coiled at 32h to seat in a groove 25a provided in the upper surface of the wippen `to bear thereagainst under spring tension. Said spring is so formed and tensioned that the arm portion between the wippen flange and the wippen engaging loop exerts a yielding downward pressure on the wippen to maintain it in contact with the capstan screw and act to rapidly return the wippen to rest posi- .tion after each stroke. That arm or portion of the spring between the wippen-and its connection with the jack is so formed and tensioned by its loop as to exert a yieldingforce upon the jack, tending to rapidly return it to rest position after each stroke.

The key l2 also carries a back check 34 for .the hammer and engages a damper lever 35. at its free end, said. lever being, pivotally supported at its oppositeendby the action rail 2l. Said lever is maintained in contact with the key by the spring 36' tov hol-d the damper head 3'!v in string dampening engagement under normal tension.

ySaid head is connected with the leverv through a connecting rod 3.8.

It will be noted that whereas the flexible jack with its seating shoulder and its associated double-acting spring may be applicable to different types of actions and pianos, herein itis illustrated as applied toa .so-called compressedaction, particularly suitable for. use in a square piano of minimum depth. Thus, it will be noted that the entire action lies in a comparatively small space in front of the sounding board and adjacent the front panel of the piano.

As best illustrated in Figs.3-6, the ange 24 is formed of a metal strap loopedk upon itself, the loop forming a bearing for receiving the hinge pin of the wippen 25. The body portion of the flange is biiurcated to receive a screw 40 for securing it to rail I9. lIhe free ends of one strap portion of the flange are bent inwardly at 4lto bite into the rail to securely fix the ilange in its adjusted position. The flangeis provided with a reduced neck portion 42. to be straddled by the bifurcatedend of the. wippen, which neck portion is looped to provide an apertured bearing 43 to receive the hinge pin 44. By means of this construction the neck portion 42 may be twisted so that the looped bearing portion 43 will extend at a predetermined angle to the body portion depending on the angle at which the action unit (wippen, hammer, etc.) extends in respect to the action rail. Thus, each flange is twisted to provide an angular hinge support according to the particular unit to which it is applied.

The invention claimed is:

1, A piano action including a hammer positioned to strike a piano string, a hammer lever therefor having a pivotal mounting, a wippen having a pivotal support at one end thereof, a jack interposed between said wippen and hammer lever for transmitting action therebetween, and a double-acting spring connected to said wippen lsupport and jack and bearing against said wippen intermediate its ends, the tension of said spring being suchl as to return saidv jack and wippen to rest position after actuation under spring tension.

2. A piano action including a hammerv positioned to strike a piano string, a hammer lever therefor having a pivotal mounting, a wippen having a pivotal support at one end thereof, a jack interposed between said wippen and hammer lever fortransmitting action therebetween, and a double-acting spring mounted for engagement with said wippen and connected with said jack formed under spring tension to-exert a yielding downwardl pressure upon saidl wippen and exerting a yielding lateral pressure upon said jack `such as to returnsaid jack and wippen to their rest positions after actuation under spring tension.

3. A piano action including ahammer positioned to strike a piano string, a hammer lever therefor having a pivotal mounting, a wippen having a pivotal support at one end thereof, a jack interposed between said wippen and hammer lever for transmitting action therebetween, and a double-acting spring having one end connected to said wippen support and the other end connected with said jack, said spring being formed with-a tension loop intermediate its ends seating against said: wippen, said spring being tensioned between said wippen support and loop to exerta yielding downward pressure upon said wippen, and being tensioned at said loop to exert a laterally directed yielding force upon said jack, whereby said spring will act to return` said jack andwippen to rest position after actuation under spring tension.

4. A piano action including a hammer positioned to strike a piano string, a hammer lever therefor, a pivotal support for said hammer lever, a wippen having a pivotal support at one end thereof` a exible `iack connected at opposite ends thereof to said wippen and lever, respec-tively, for transmittingaction therebetween, and a double-acting spring having one end connected with said wippen support and the other end connected with said jack, said spring having an intermediate portion bearing against said wippen to return said wippenv and iiexed jack to. rest position under springA tension after actuation.

5. A piano action including a hammer positioned to strike a piano. string'y a hammer lever therefor, a pivotalsupport for. saidhammer lever, a wippen having a pivotal support at one end thereof, a jack member pivotally connected at one endv thereof to, said wippen, a link pivotally connecting the oppositeend, of' saidjack member to, said hammer lever fory transmitting action from said wippen to said lever and iiexing at the pivotal Iconnection between said jack member and link member to provide a let-off action for said hammer, and a spring having one end anchored to said wippen support to extend into engagement with said wippen, tending to depress said wippen under spring tension to rest position, said spring being looped intermediate its ends and extending therefrom for connection at its free end with said jack member adjacent its pivotal connection with said link member, said loop portion exerting spring tension upon said jack member, tending t-o return it to rest position after exing.

6. A piano action including a hammer positioned to strike a piano string, a hammer lever therefor having a pivotal mounting, a wippen having a pivotal support at one end thereof, a jack interposed between said wippen and hammer lever for transmitting action therebetween, and a double-acting spring support for connection with said wippen and jack, said spring being formed to exert spring tension upon said wippen in one direction and upon said jack in a dierent direction, tending to return said jack and wippen to their rest positions after actuation.

7. A piano action including a hammer positioned to strike a piano string, a hammer lever therefor, a pivotal support for said hammer lever, a wippen having a pivotal support at one end thereof, a jack member pivotally connected at one end thereof to said wippen, a link pivotally connecting the opposite end of said jack member to said hammer lever for transmitting action from said wippen to said lever and iiexing at the pivotal connection between said jack member and link member, a double-acting spring connected to said wippen support and jack member formed with a loop portion intermediate its ends bearing against said wippen, the tension of said spring being such as to return said jack and wippen to their rest positions under spring tension, and a shoulder formed on said jack member engageable with said link member to limit the relative movement therebetween upon being returned to rest position under tension of said spring, the relation of said shoulder and link being such as to provide a rest to maintain them in hammer actuating position while permitting flexing after actuation.

FRANCIS C. SOCIN.

msFmmNcEs CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 317,660 Menges May 12, 1885 492,386 Chapman Feb. 28, 1893 519,166 Wallace May 1, 1894 537,145 Felldin Apr. 9, 1895 1,353,905 Gertz Sept. 28, 1920 1,990,764 Wessell Feb. 12, 1935 2,032,745 Finholm Mar. 3, 1936 2,156,913 Finholm May 2, 1939 

